There’s no getting around this one: The Dakar Sixfifty B Comp is taller than a 26″ bike and some of our 650b bikes. With unsagged BB height at 13.5 inches the Jamis Dakar sits taller than some of our 150mm travel 650b bikes as it reflects some of its East Coast roots. The top tube does what it can to slope downward before the seat tube but standover height can be a concern for shorter riders on very technical terrain. 5″ of suspension coupled to the larger 650B wheels results in a bike with a fairly high center of gravity.

Getting into the saddle reveals a chassis that feels more compact than it looks from afar. The reach to the bars is a bit more stretched out than what’s found on your average 26″ wheel-equipped all-mountain bike but none of that cross-country bent backing stuff found here either. Fit and finish is surprisingly good- little touches like lock-on grips and 15QR remind that Jamis has been at this game for quite a while.

Blast-Off

So the big question- what’s it like to drop the hammer on the Dakar Sixfifty B? The answer in a single word would be smooth. That 30-speed geartrain means depending on your legs and lungs, you’ll always have a gear combo that feels custom tailored to your needs. However, this isn’t a wispy XC bike no matter how you slice it so there’s little point in pushing a big gear until you’re seeing spots. The Dakar is all about flow and those slightly larger wheels only extenuate this fact. We found the optimal means of enjoying “big B” was to start out in a low gear combo, to stay seated, and gradually build a nice head of steam. In doing so the charms of the 27.5-inch wheels, the rigidity of the 15QR and the benefits of just over 5-inches of suspension pay dividends.

Speaking of wheels; that seems to be what everyone wants to hear about so let us do our best to enlighten you as well. As you would probably suspect, rolling on 650Bs isn’t quite as dramatic as the transition to full 29er for the average steady 26″ rider but nor would it be mistaken for just another 26er either. Confused? Don’t be. All we’re saying is that the 650B has a unique feel- only slightly slower rolling than a 26″-wheel but quite sure-footed in roots and ruts. 29er diehards should really do themselves a favor and give a 650B a go when it comes time to upgrade due to the fact that they feel much livelier, especially during dead take offs. 26″ riders on the fence about going bigger absolutely need to give one a test ride as many of the disadvantages of 29″ wheels are toned down here.

Odds & Ends

As much as we’d like to get away with just spilling a little rhetoric about wheel sizes, there’s surely a lot more about the experience of riding the Jamis that you’d like to hear about. Let’s start with the tires shall we? Kenda Nevegals are always a favorite spec for the MBT test crew and the slightly larger diameter does nothing to change that fact. These meats are perfect for the frequent transitions from hardpack to roots, from roots to mud, and mud to sand that we east coasters call trails. They may be overkill for riders who frequent concrete-hard packed singletrack, endless flat rocks or paved bike paths but for everyone else, they’re simply magic.

Cornering can be a mixed bag depending on how you treat the Sixfifty B. As we stated above, it’s a taller bike so it likes to be finessed around turns and certainly responds more favorably to this than attempting to stuff it into a corner then power out with your legs. One of the major benefits to larger wheels is increased lean-over ability so capitalize by maintaining your cadence and leaning it into the curves.

Climbing is never effortless on a 30+ pound bike but again relying upon the bike’s copious gearing makes the experience so much less painful than it could be. We found the best way up those ugly grinders was to stay seated, find a nice comfortable low gearing combination and to spin away. You’ll never find those XC-style spurts of forward momentum here so there’s no sense in wasting energy looking for it.

Descending is where the Dakar reminds you that the word “nervous” isn’t a part of its vocabulary. Sure-footed 27.5″ wheels with a tendency of tracking true even in the rough stuff, 5.1″ of suspension and those pinpoint accurate 15QRs make going down hill a blast. This bike likes to hold a line! You’ll find confidence you never even realized you were lacking the first time gravity grabs a hold of that front wheel.

It is stable but it is not a quick bike as the chainstay length and wheelbase are a hair on the long side. It is a confident descender but it’s not plush or slack. It can climb but will not rocket up hills with this weight, suspension and no stable platform shock. So it’s not brilliant at any one thing but it is a balanced xc trail bike.

Braking is adequate on the trails and a bit underpowered on the high-speed descents. Fortunately, since the Avid Elixir 3s offer decent actuation, steady modulation and a nice feel at the levers, this is a fairly cheap upgrade in the form of larger rotors if shuttle running is on your Sixfifty B agenda.

Conclusion

The way we figure it, there’s two ways to approach the Jamis Dakar Sixfifty B: The first is to become obsessed with the gimmick of wheel size and to base your entire opinion of the bike upon it’s choice of “intermediate” sized 650B wheels. The second is to forget all about the media-created controversy of wheel diameter and to simply let the ride tell its story. It is the latter that we tried to keep in mind while testing and the good news with that is we came away with a lot to appreciate about the Dakar’s manners. This is a very versatile trail bike with a good honest spec sheet and at a solid price point. Whether or not the 650B wheel size is the wave of the future or just a passing fad is irrelevant to this bike and should be to you too.

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I LOVE, LOVE, LOVE my Jamis Killer B!! I’m a pretty slow, cautious rider – but this bike gives me the confidence to ride faster, harder, better! I’m not a great bike mechanic – but even I could adjust the suspension easily. I would highly suggest anyone interested in a 650B should take one for a ride!!